Pull-rod clamp



June 24, 1930. DURNELL ET AL 1,768,038

PULL ROD CLAMP- Filed May 18, 19 29 mvEmToR wyTusssn ALITQRNQIY Patented June 24; 1930 UNITED res HAROLD GIBSON DURNELL AND SAMUEL T. STEEL, OF BARTLESVILLE, OKLAHOMA PULL-ROD CLAMP Application filed May 18, 19-29. Serial No. 364,233.

This invention relates to a combination clamp used with pull rods of pump mechanism of oil wells and the like, the general object of the invention being to provide a simple, strong and durable clamp in which the two sections of the clamp are connected together by two bolts which are so arranged as to cause the sections to exert equal tension and pressure on the pull rod and the bolts and to provide means whereby the clamp can be used with upset end pull rods or with.

regular headed pull rods.

Another object of the invention is to provide recesses in the U bolt passageways so that the heads of the U bolt will be enclosed by the clamp, this arrangement also preventing the U bolt from slipping out of position.

A further object of the invention is to provide the clamp with a smooth face at each end thereof for the purpose of presenting a flat surface to engage a knockoff block.

This invention also consists in certain other features of construction and in the combination and arrangement of the several parts, to be hereinafter fully described, illustrated in the accompanying drawings and specifically pointed out in the appended claims.

In describing the invention in detail, reference will be had to the accompanying drawings wherein like characters denote like or corresponding parts throughout the several views, and in which Figure 1 is a view of the improved clamp used with an upset end pull rod.

Figure 2 is a similar View, but showing one of the sections removed.

Figure 3 is a View similar to Figure 2, but showing a regular pull rod used with the device.

Figure 4 is a section on line 4-4 of Figure In these views, the clamp A is shown as composed of the two sections 1 and 2. Each section is formed with a recess 3- which extends from one end to the other of the inner face of the section, the recess being of semicircular shape in cross section and having an enlarged part 3 at one end thereof. Each section is also provided with a pair of recesses 4 on its inner face, one on each side of the recess 3, these recesses 4 also extending from one end to the other of the section and each recess 4 has an enlargement 4 adjacent each end thereof. Thus when the two sections' are placed together, the recesses 3 and 4 will form passages, the central passage formed by the recesses 3 receiving the pull rod 5 and the passages formed by the recesses 4 receiving the limbs of the U bolt 6. The two sections are connected together by the two bolts 7 which pass through holes 8 and 8' formed in the sections, each hole being located between the recess 3 and each recess 4 and the holes are arranged closer to one end of the section than the other. The hole 8' in each section is preferably of rectangular shape in cross section, while the hole 8 is of circular shape in cross section. The holes 8" are adapted to receive the square portions of the bolts, as shown in Figure 4, it being seen that the bolts are reversely arranged. By

placing the bolt holes closer to one end of the device than theother, there is no danger of improperly placing the sections together.

The enlarged part of the passage formed by the recesses 3 is adapted to receive a pull rod of the upset end type, whereby the enlargement 5 of the pull rod fits in the enlarged part of the passage, as shown in Figure 2. By reversing the clamp, the regular pull rod 5", which is formed with a flat head 5", can be used with the device, as shown in Figure 8. The enlargements 4receive the heads 6 at the ends of the U bolt, and by providing two pairs of these enlargements, the clamp can be reversed without changing its relative position with the U bolt.

As before stated, by using two bolts arranged as shown, equal tension and pressure may be applied to the bolts and the pull rods, which cannot be done where four bolts are used and when the four bolts are used, the one having the greatest tension usually breaks or strips its threads. It will also be seen that the clamp has flat endsso that it can be used with a knock-off block, as these flat ends present a flat surface to the block.

By using but two bolts arranged as shown, one bolt may be tightened and then when the other bolt is tightened, the clamp sections Will grip the pull rod and the U bolt With a perfectly balanced action.

It is thought from the foregoing description that the advantages and novel features of the invention Will be readily apparent.

It is to be understood that changes may be made in the construction and in the combination and arrangement of-the several parts, provided that such changes fall Within the scope of the appended claims.

What We claim is V 1. A clamp of the class described compris- 'ing two sections having recesses on their inner faces forming a centrally arranged passage and tWo side passages, the side passages receiving the limbs of a. U bolt and the central passage receiving a pull rod, bolts for clamping the sections together, said central passage having an enlargement at one end whereby a pull rod having an enlargement thereon can be used with the clamp, the enlargement fitting in the enlarged part of the passage and each side passage having an enlargement adjacent each end thereof for receiving the head at the end of each limb of the U bolt, the heads fitting in the enlargeinents adjacent one end of the clamp when the U bolt extends through the opposite end and said heads fitting in the other enlargements when the bolt is reversed, each end of the clamp being fiat, whereby either end of the clamp can be placed against a knock-elf block.

2. A clamp of the class described comprising two sections having recesses on their 1nner faces forming a centrally arranged passage and two side passages, the side passages receiving the limbs of a U bolt and the central passage receiving a pull rod and a s1nglepa1r of bolts for clamping the sections together,

each bolt passing through the space between the central passage and a side passage, the bolts passing through the sections at points slightly beyond the transverse center of the clamp. p

In testimony whereof We affix our signatures.

HAROLD GIBSON DURN ELL. SAMUEL T. STEEL. 

